1. Field of the Invention
The present invention relates to a method of manufacturing an electromechanical transducer layer, a method of manufacturing an electromechanical transducer element, an electromechanical transducer layer, an electromechanical transducer element, an inkjet head and an inkjet recording apparatus, and more specifically, to a method of manufacturing an electromechanical transducer layer by an inkjet method, a method of manufacturing an electromechanical transducer element, an electromechanical transducer layer, an electromechanical transducer element, an inkjet head and an inkjet recording apparatus.
2. Description of the Related Art
An inkjet recording apparatus has many merits such that noise is low, capable of printing fast, capable of using a variety of liquids as ink and capable of forming an image on a cheap recording medium such as a paper. Therefore, the inkjet recording apparatus has been used for many kinds of image recording apparatuses such as a printer, a copying machine, a facsimile machine or the like.
For the inkjet recording apparatus, an inkjet head (liquid discharging head) is used. The inkjet head includes a nozzle plate provided with nozzles for discharging ink droplets, pressure rooms to be in communication with the nozzles respectively, and pressure generating units to apply pressure to ink in the pressure rooms.
The pressure generating unit includes an electromechanical transducer element such as a piezoelectric element or the like or an electrothermal element such as a heater or the like for applying pressure to the ink in the pressure room, or an energy generating unit including a vibration layer which composes a wall of the pressure room and an electrode provided to face the vibration layer.
The pressure generating unit using the electromechanical transducer element which is a so-called “piezo type” is widely developed as it is capable of functioning fast, providing a high density alignment and using liquids of a large variety of viscosities.
The electromechanical transducer element includes a stacked structure of a lower electrode, an electromechanical transducer layer and an upper electrode. By applying voltage between the lower electrode and the upper electrode, the electromechanical transducer layer deforms to press a vibration layer at the pressure room and discharge ink in the pressure room from the nozzle.
The inkjet head includes the plural pressure rooms. For individually applying pressure to the pressure rooms, the plural electromechanical transducer elements are provided for the plural pressure rooms, respectively.
For the electromechanical transducer layer, a mixed metal oxide layer which is mainly composed of metal oxide such as zirconate lead titanate (PZT) ceramics or the like is used.
For a method of manufacturing the electromechanical transducer layer of an electromechanical transducer element composed of a stacked structure of a lower electrode, a ceramics layer as the electromechanical transducer layer, and an upper electrode, it is disclosed that the ceramics layer is formed by two or more of inkjet heads (patent document 1). In this method, two or more solutions each including a source material are separately discharged from the different inkjet heads to form the ceramics layer on the lower electrode.
Further, it is disclosed in patent document 2 that a ferroelectric layer is formed by discharging from an inkjet head a solution including a material for forming the ferroelectric layer adjusted for the inkjet head.